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    Colorado Criminal Law – The Principle of Aiding and Abetting – and “The Mere Presence Doctrine”

    by Colorado Criminal Defense Lawyer – and Teacher – H. Michael Steinberg


    The “Mere Presence During The Crime” Issue

    1. Merely standing by, even if standing by with knowledge concerning the commission of a crime, does not make a person a principal to a crime.
    2. Once again – the mere presence at the scene of a crime, without participation, does not make a person a principal to a crime.
    3. One who does not actively commit the offense, but who aids, promotes, or encourages the commission of a crime by another person, either by act or counsel or both, is deemed to be a principal to the crime if he/she knowingly did what he/she did either with criminal intent or with knowledge of the other person’s intent.
    4. To aid or abet another in the commission of a crime implies a consciousness of guilt in instigating, encouraging, promoting, or aiding in the commission of that criminal offense.

    The History Behind The Rule

    At common law, the parties to a felony were classified in accordance with their degree of participation.

    Principals were classed as either: first or second degree;

    Accessories were designated as either before or after the fact.

    The principal in the first degree was the criminal actor himself, the person whose conduct directly engendered the criminal result. An individual who aided and abetted the principal in the first degree was punishable either as a principal in the second degree or as an accessory before the fact, depending upon whether the individual was present, either actually or constructively, at the commission of the crime. An accessory after the fact was an individual who, cognizant of the completed felony, rendered aid and comfort to the felon for the purpose of hindering his apprehension, conviction, or punishment.

    In Colorado, these distinctions have been statutorily abolished. Those formerly classified at common law as principals in the first and second degree, as well as those classified as accessories before the fact, are statutorily defined as principals. Those classified at common law as accessories after the fact are statutorily denominated as accessories.

    Personal Presence At The Crime Does NOT MATTER

    An aider and abettor does not personally need to intend to commit a crime to be liable as a principal. A person may also be liable as a principal for aiding and abetting the perpetrator knowing of the perpetrator’s intent to commit the crime.

    Because Colorado provides that aiders and abettors are liable as principals, criminal liability must extend beyond persons who intend to commit a crime to persons who aid and abet the

    perpetrator knowing of the perpetrator’s intent to commit the crime. Participation in the commission of a crime remains a question of fact, and may be established by circumstantial proof.

    However, more than consent to, or acquiescence in, the criminal acts of another is required to constitute participation; consent or acquiescence involves cognitive or mental activity which, unless communicated to the perpetrator of the offense, does not serve to aid and abet him in its commission.

    Express or Implied Consent To Participate In The Crime

    No one can be properly convicted of a crime to the commission of which he has never expressly or impliedly given his assent. To hold otherwise would be contrary to natural right and shocking to every sense of justice and humanity. When the accused is present and aiding and abetting another in its commission, he may be considered as expressly assenting thereto, so, where he has entered into a conspiracy with others to commit a felony or other crime under such circumstances as will, when tested by experience, probably result in the unlawful taking of human life, he must be presumed to have understood the consequences which might reasonably be expected to flow from carrying into effect such unlawful combination, and also to have assented to the aiding of whatever should reasonably or probably be necessary to accomplish the objects of the conspiracy, even to the taking of life.

    But further than this the law does not go; for if the accused in such case has not expressly assented to the commission of the crime, and the unlawful enterprise is not of such character as will probably involve the necessity of taking life in carrying it into execution, there can be no implied assent, and consequently no criminal liability.

    The mere presence of the accused at the scene of the homicide does not make him a criminal; he may have known that a crime was committed, yet, if he did not participate in it directly or indirectly, or encourage the party doing the killing, his mere presence would not constitute him a principal in the transaction or connect him criminally with the killing.

    What About Abandonment Of The Crime – Criminal Act?

    Aiding and Abetting – the Defense of Abandonment

    It is a defense to the charge of aiding and abetting that a person abandoned the commission of the  alleged crime. However, the responsibility of one who has aided and abetted in the commission of a crime, or engaged in a criminal undertaking, does not cease unless, within time to prevent the commission of the contemplated act, he/she has done everything practicable to prevent its consummation. It is not enough that he/she may have changed his/her mind, and tried when too late to avoid responsibility.

    He/she will be liable if he/she fails within time to let the other party/parties know of his/her withdrawal, and unless he/she does everything in his/her power to prevent the commission of the crime.

    Since the claim that the defendant abandoned participation in the crime charged, notified others engaged in the criminal endeavor of the withdrawal, and attempted to prevent the commission of the crime is a defense, the onus of producing evidence sufficient to raise the defense of abandonment remains on the defendant, unless the evidence of the prosecution has raised the issue. If the defendant fails to adduce any evidence that tends to prove that the defendant’s participation in the criminal venture was abandoned, or if the defendant’s evidence is insufficient as a matter of law, then the issue of abandonment of the crime is not presented, and no instruction should be given.

    For more information on this concept CLICK HERE


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    H. Michael Steinberg Esq.
    Attorney and Counselor at Law
    The Colorado Criminal Defense Law Firm of H. Michael Steinberg
    A Denver, Colorado Lawyer Focused Exclusively On
    Colorado Criminal Law For Over 40 Years.
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    8400 East Prentice Ave, Penthouse 1500
    Greenwood Village, Colorado, 80111
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